Thermophysical characterization of concrete reinforced with baobab trunk fibers (Adansonia digitata L.) for thermal insulation of buildings

This work deals with characterizing concrete based on baobab trunk fibers for thermal in- sulation in buildings. The aim is to study the effect of the fiber content and the type of fiber treatment on the hygroscopic and thermo-physical properties of the concrete. Therefore, two types of treatment were carried out: an alkaline treatment and a thermo-alkaline treatment. Hygroscopic test results (34.25% to 54.92% for fiber content ranging from 14% to 28%) show that adding fibers to concrete makes them more sensitive to water. However, thermochemical treatment of the fibers reduces this water sensitivity. The thermal conductivities of concrete range from 0.202 to 0.086 W/m.K for the same fiber content. These results show that these biomaterials can be used in construction to improve building insulation. In order to contribute to the reduction of energy consumption in building exploitation, we proposed to study the properties of a bio-based building material. This work deals with the characterization of a concrete based on baobab trunk fibers for thermal insulation in buildings. The aim is to study the effect of the fibers content and the type of fibers treatment on the hygroscopic and thermo-physical properties of the concrete. Therefore, two types of treatment were carried out : an alkaline treatment and a thermo-alkaline treatment. The hygroscopic results show that these concretes are more sensitive to water than the control concrete. This high water absorption of these bio-based materials restricts their application in the construction field. However, we noted that the thermochemical treatment of the fibers better contributed to the reduction of this water sensitivity of the concretes. The thermal conductivity varies between 0.202 W.m-1.K-1 and 0.086 W.m-1.K-1. These results show that these biomaterials can be used in construction to improve insulation in buildings. The experimental thermal conductivities are close to those of the self-consistent model applied to the concrete. Baobab fibers – Cement -Thermal conductivity -Density -Water absorption -Self-consistent.